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Pharmaceuticals in Drinking Water
- Recent newspaper reports discussed the presence of pharmaceuticals in drinking water throughout the country as well as in Philadelphia's drinking water. Is our drinking water still safe to drink?
Yes, absolutely. Our drinking water not only meets all federal and state regulations for clean and safe drinking water but surpasses even those requirements. The city was one of the original participants in the Partnership for Safe Water, a voluntary, nationwide program ensuring the highest standards for water treatment plant performance. Through our Partnership efforts, advanced research and award-winning Source Water Assessment Program, we stay at the forefront of our field with the primary goal of ensuring safe and clean drinking water for our customers.
- Many cities have not sampled for pharmaceuticals in their drinking water. Did we have any special concerns that caused us to sample?
No. We had no special concerns nor were we required to sample under federal or state law. The city was already a leader in Source Water Protection, the activities needed to protect the quality of our rivers and streams from which we obtain our drinking water. In that role, we had the opportunity to participate in some of the earliest national research studies on pharmaceuticals in source water and drinking water. We have since developed our own internal research program to continue our advanced monitoring and research efforts.
- How do pharmaceuticals get into drinking water?
The simple answer is people. People in Philadelphia, nationwide and throughout the world now take more pharmaceuticals, both prescription and over the counter, than ever. Only a small portion of these pharmaceuticals are absorbed in the body. The rest is flushed, making its way into rivers and streams throughout our region and worldwide. Animal waste and agricultural runoff also contributes pharmaceuticals to our waters. These rivers and streams are our source waters, the water we withdraw from to produce our drinking water.
- What pharmaceuticals did we find and how much did we find?
Not surprisingly, we found pharmaceuticals that are in widespread use in society, such as caffeine, acetaminophen (Tylenol), nicotine, and cough medicine. We were only able to see these compounds because we employed sophisticated new measurement technologies. These compounds are at such low concentrations that they cannot be detected unless the most advanced methods are used.
Only a few specialized laboratories in the country have these capabilities. We partnered with these laboratories to achieve these extremely low detection limits. Even when using the most sensitive measurement methods, we seldom find these compounds in our drinking water samples. However, we take a conservative approach to describing our findings so that if a compound was detected even just once, in dozens of samples, it was counted.
No results in excess of nanograms per liter (or parts per trillion), have ever been
observed in our drinking water. To provide some tangible sense of how low these
observed concentrations are, we will use caffeine and acetaminophen (Tylenol's
active ingredient) as examples (note that caffeine was the compound found at the
highest concentration in our studies). Assuming the highest-ever observed PWD
concentration levels, a person would need to drink eight glasses of water a day for
more than 1,200 years to obtain the amount of caffeine in a single cup of coffee
(100 mg), or for 40,000 years to obtain the equivalent of a single infant dose (80 mg) of Tylenol. These are the types of levels we are finding. There is currently no indication that such extremely low concentrations pose any public health risk.
Although originally reported to the Associated Press that 56 pharmaceuticals were found in our drinking water, only 17 compounds were actually detected from among the 70 we have looked for over the course of our 4 years of monitoring.
- Does Philadelphia have more pharmaceuticals in our drinking water than other cities?
No. The issue of pharmaceuticals in drinking water exists throughout the country and the world. Wherever people or animals are taking pharmaceuticals, trace amounts of these substances will make it into the surrounding watershed. What is unique about Philadelphia is that we have chosen to participate actively in this new area of research, as we have done with previous issues, to ensure that our drinking water remains healthy and safe for generations to come.
- What is PWD doing to ensure our drinking water remains safe?
We will continue monitoring pharmaceuticals in our water supplies and partnering in regional and national research efforts to enhance our knowledge and understanding. As always, our Source Water Protection Program and our drinking water plants will be operated to ensure the highest level of public health and safety. Lastly, in today's world, the media is often the most effective way to raise awareness about an issue, although the message is outside existing public dialogue. Engaging the public to better understand their concerns and to properly direct our education strategies is a challenge that we embrace.
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What is being done nationwide to address this issue?
The U.S. EPA evaluates the need for new drinking water contaminant regulations through a program called the Contaminant Candidate List (CCL) which periodically identifies and lists contaminants that may be present in public water supplies and may adversely impact public health. Occurrence and health effects information for substances on this list are carefully evaluated to determine whether federal regulations are needed. Because of the extremely low concentration levels of detected pharmaceuticals in water and the lack of indication for human health impacts, these substances have not been listed for regulatory consideration to date.
However, the EPA and other organizations are conducting and/or supporting a large amount of research on this topic. Research areas include development and improvement of testing methods, monitoring water quality, evaluating the effectiveness of treatment processes for pharmaceutical removal, and potential environmental and human health impacts.
Efforts to keep unused pharmaceuticals out of the water supply are growing rapidly in the U.S. and you can help. Pay attention to how you dispose of unused medications. Look for take-back programs that may be established near you soon, either through pharmacies, or through household hazardous waste collection programs. Generally speaking, pharmaceuticals are not to be flushed down the toilet or poured down the drain. Specific disposal instructions are provided by the Office of National Drug Control Policy and the U.S. Fish and Wildlife service at the following links:
http://www.whitehousedrugpolicy.gov/drugfact/factsht/proper_disposal.html
http://www.fws.gov/southeast/news/2007/r07-050.html
- Should I be buying bottled water or use a home treatment device?
No. Our water is healthy and safe. However, if you do choose to use bottled water, please be aware that these products vary considerably with respect to water source, water quality and cost. Customers should shop for bottled water wisely and store it properly. Internet sites that can help customers become more knowledgeable about bottled waters include NSF International at www.nsf.org/consumer, the International Bottled Water Association (IBWA) at www.bottledwater.org and the US Food and Drug Administration (FDA) at www.cfsan.fda.gov/~lrd/bot-h2o.html. An interesting discussion with further links can be found at http://www.safedrinkingwater.com/alerts/alert080207.htm.
The most commonly used home treatment devices, which involve filtering water through granulated carbon, are not highly effective at removing trace levels of pharmaceutical compounds. More elaborate and much less commonly used devices that employ reverse osmosis technology may partially remove these substances. It is important to understand that, for all types of home treatment devices, water quality degradation (both chemical and microbiological) may result from improper maintenance. Therefore, manufacturers' instructions must be followed carefully when using any such device.
- Where can I go for additional information?
Additional information can be found at the following websites:
U.S. Environmental Protection Agency
http://www.epa.gov/ppcp/
http://www.epa.gov/safewater/ccl/
http://www.epa.gov/safewater/ucmr/index.html
American Water Works Association (AWWA)
http://www.drinktap.org/consumerdnn/Home/WaterInformation/WaterQuality/PharmaceuticalsPPCPs/tabid/73/Default.aspx
Awwa Research Foundation
http://www.awwarf.org/research/TopicsAndProjects/topicSnapshot.aspx?topic=EDCS
U.S. Food and Drug Administration
http://www.fda.gov/cder/drug/default.htm
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